Space discharge device



May 29, 1945. H. OLKEN SPACE DISCHARGE DEVICE Filed May 19, 1943 alli;

INVENTOR BY /7)/7A/V OL/fE/V 7/ WMV ATTORNEY Patented May 29, 1945 UNITED STATES PATENT OFFICE SPACE DISCHARGE DEVICE I Hyman Olken, Washington, D. C.

Application May 19, 1943, Serial No. 487,563

8 Claims.

This invention, which is a continuation-in-part of my co-pending application, Serial No. 438,679, filed April 13, 1942, relates to electron discharge devices of the so-called beam type and its principal object is to provide a novel arrangement for deflecting the beam relative to an anode in the device, thereby changing the electron flow in the anode-cathode circuit.

A more specific object is to provide a. device of the character described in which deflection of the beam is controlled in accordance with the position of an electrode located outside of the device,

Such a device can be used for various applications in which a, changeiin electric current in response to a variation in a condition is desired, the particular application illustrated being for motor control in which it is desired to control the direction of rotation of the motor in accordance with a change in a condition such as the change in the position of a sensitive instrument pointer.

The foregoing and other objects of the invention will become more apparent from the detailed description to follow when considered with the accompanying drawing, in which:

Fig. 1 is a diagrammatic view of one form of discharge device embodying thev invention;

Fig. 2 is also a diagrammatic view of another embodiment of the invention;

Fig. 3 is a modification of the device shown in Fig. 2; and

Figs. 4 and 5 are further embodiments illustrating the invention.

Referring now to Fig, 1, the discharge device comprises an envelope ID, the upper surface of which is depressed arcuately at the central portion. Within the envelope I0 is disposed a cathode II and a pair of anodes I2 and I3, each of which is spaced at the same distance from the cathode II but on opposite sides thereof,

Connected in the cathode-anode circuit including anode I2 is one motor field winding I4 and the motor armature l5. In the other cathode-anode circuit including the anode I3 is a second motor field Winding I6 and the armature I5. Suitable anode potential for these circuits is furnished by any adequate source such as the battery II.

For focussing the electron stream from the cathode II into two beams, one between cathode II and anode I2 and the other between cathode II and anode I3, and for also controlling the deflection of these beams relative to their respective anodes, I provide a pair of electrodes I8 and I9. Electrode I8, which occupies a fixed position, is located inside of the envelope ID and is placed very close to the cathode I I. Electrode I9 is also disposed very close to cathode II but is located outside of the envelope I0 at the depressed central portion thereof and is mounted on an instrument pointer 20 and rotatable with the latter about an axis 0.

Electrodes I8 and I!) are similarly and negatively charged relative to the cathode II by suitable biasing means such as battery 2 I.

The operation of the device should now be apparent. With the movable electrode I9 in the position shown in Fig. l, the axes of the electron beams are substantially normal to a'line passing through electrodes I8, I9 and cathode I I. Consequently electron flow between cathode I I and anode i2 is the same as that between cathode I! and anode I3 and the two motor field windings I4 and IBare equally energized producing equal field strengths. However, it will be seen that current flow through the two fields are in opposite directions with respect to each other and thus the field fluxes neutralize one another with the result that no field is produced and thearmature. remains stationary.

In the event that the instrument pointer 20 should move in a counter-clockwise direction, the electrode I9 will move similarly and cause the electron beam between cathode II and anode I2 to be deflected downwardly. Part of this beam would thus move off anode I2 resulting in a decrease in current flow through the circuit including field winding I 4. This unbalances the two opposed field windings I4 and I6 thereby causing the armature I5'to rotate in one direction.

Should the pointer 20 move clockwise, causing similar movement of electrode I9, the electron beam between cathode II and anode I3 will be deflected downwardly and lessens the current fiow through field winding I6. This unbalances the field windings I4'and I6 in the other direction thereby effecting rotation of the armature I5 in an opposite direction.

In the arrangement shown in Fig. 2, the basic arrangement of parts is the same as those in Fig. l and the same reference characters have been utilized to indicate like parts. In addition, the Fig. 2 structure includes accelerating electrodes 22-22 between cathode II and anode I2 and similarly placed electrodes 23-23 between cathode II and anode [3. In this arrangement, a deflection in either of the beams, results in much sharper reduction in'current flow through the field windings I4 and I6.

The arrangement shown in Fig. 3 is much the same as that shown in Fig. 2 with the exception that beam current deflected to the accelerating electrodes 2222' and 23-23' is utilized to increase the differential effect in the field windings l4 and I6. Thus, beam current intercepted by electrodes 22-22 is added to the current already flowing through winding l6 as the current flow through windin I4 is decreased. In a similar manner, beam current intercepted by electrodes 23-23 is added to the current already flowing in winding M as the current flow through winding 16 is decreased.

Thus a deflection of the electrode l9 would not only reduce current in one field winding but would add the difierence to the current traversing the opposed field winding. This obviously increased the sensitivity of the control action.

In the modification shown in Fig. 4, a somewhat different arrangement of parts is utilized. Instead of having two beams, only one is employed and is split between two anodes 24 and 25 placed side by side. When electrode I9 i in a central position, the electron beam is split equally between the plates 24 and 25 and an equal amount of current flows in the windings l4 and Hi. However should the beam be deflected either upward or downward as the case may be, the current flow through one of the field windings will be decreased while the other is increased thus bringing about the desired diflerential action.

In the arrangement shown in Fig. 5, the electron stream from a cathode 26 is divided into two equal streams by identical acceleratin screen electrodes 21 and 28 at the same voltages. Two other screens, 29 and 30 are positioned behind screens 21 and 28 respectively, with the wires of screen 29 registering with those of screen 21 and the wires of screen 30 registering with those of screen 28. By adjusting to suitable relation the voltages on these screens, the streams of electrons coming through the openings in screens 21 and 28 will be focussed to be in a straight or even divergent beam as they come through the openings in screens 2,9 and 3|]. The relative spacing and voltages of screens 21, 28 and 29, 30 are furthermore so chosen that the accelerated electrons go through the openings in screens 29 and 30 but only slightly beyond and then turn back. The streaming electrons being slowed up near screens 29 and 30, a good part of them will be absorbed by screens 21 and 28. A plate 3| outside the tube and revolved with the instrument pointer pivoted at is charged to a high negative voltage. Consequently the electron stream to the parts of screens 29 and 39 underneath the plate 3| are retarded and reverse before reaching them. Hence if plate 3| is deflected from center, say to the right, so that it projects more over screen 30 than screen 29, the current to screen 30 will be reduced below normal while the current to screen 29 will be raised above normal. This brings about the desired differential eifect in the motor field windings I 4 and l 6.

In conclusion, I wish it to be understood that other changes and modifications in the structures shown and. rearrangement of parts may become apparent to those skilled in the art and may be made without departing from the spirit and scope of the invention as defined in the appended claims.

The invention described herein may be manufactured and used by or for the Government of the United States of America for governmental purposes without the payment of any royalties thereon or therefor.

Having thus fully described my invention, I claim:

1. An electron discharge device comprising an envelope, a cathode for emitting electrons, a pair of charged electrodes disposed on opposite sides of and closely adjacent to said cathode for forming said electron emission into a beam, an anode for receiving said beam, and means for moving one of said electrodes relative to the other whereby said electron beam may be deflected relative to said anode to vary the amount of current flowing in the anode-cathode circuit of said device.

2. The combination in claim 1 wherein one of said electrodes is fixed and disposed interiorly of the envelope and the other electrode is movable and disposed exteriorly of the envelope.

3. An electron discharge device comprising an envelope, a cathode for emitting electrons, a pair of anodes disposed on opposite sides of said cathode, a pair of charged beam forming electrodes also disposed on opposite sides of said cathode and closely adjacent thereto but on an axis substantially normal to the axis through said cathode and anodes, and means for moving one of said electrodes relative to the other whereby one or the other of said beams may be deflected relative to its respective anode to vary the amount of current flowing in the respective anode-cathode circuit.

4. The combination in claim 3 wherein one of said electrodes is fixed and disposed interiorly of the envelope and the other electrode i movable and disposed exteriorly of the envelope.

5. An electron discharge device comprising an envelope, a cathode for emitting electrons, a pair of anodes disposed on opposite sides of said cathode, a pair of charged beam forming electrodes also disposed on opposite sides of said cathode but on an axis substantially normal to the axis through said cathode and anodes, accelerating electrodes disposed between said cathode and each of said anodes, and means for moving one of said electrodes relative to the other whereby one or the other of said beams may be deflected relative to its respective anode to vary the amount of current flowing in the respective anode-cathode circuit.

6. An electron discharge device comprising an envelope, a cathode for emitting electrons, a pair of anodes disposed on opposite sides of said cathode, a pair of charged beam forming electrodes also disposed on opposite sides of said cathode and closely adjacent thereto but on an axis substantially normal to the axis through said cathode and anodes, accelerating electrodes disposed between said cathode and each of said anodes, means for moving one of said electrodes relative to the other whereby one or the other of said beams may be deflected relative to its respective anode to vary the amount of current flowing in the respective anode-cathode circuit, and means for adding the current intercepted by the accelerating' electrodes disposed between said cathode and one anode to the current flowing in the cathode-anode circuit which includes the other of said anodes.

'7. An electron discharge device comprising an envelope, a cathode disposed at one end of said envelope for emitting electrons, a pair of anodes disposed at the other end of said envelope, an anode-cathode circuit for each of said anodes, a pair of charged beam forming electrodes disposed on opposite sides of said cathode and means for moving one of said electrodes relative to the other whereby said electron beam may be deflected relarelative to said anode comprising a pair of charged electrodes disposed on opposite side of said cathode, one of said electrodes being movable and disposed interiorly of said envelope and the other electrode being disposed exteriorly of said envelope.

HYMAN OLKEN. 

